1. Field of the Invention
This invention relates to vinyloxazoline monomers and copolymers and their preparation.
2. Background Art
This invention relates to new organic compounds, including 2-(2allyloxy-1-methylethyl)-2-oxazoline (AOx) and 2-(vinylbenzyloxy-1-methylethyl)-2-oxazoline (SOx). Its method of preparation comprises condensing 2-(3-hydroxy-2-propyl)-2-oxazoline with allyl chloride and vinylbenzyl chloride, respectively, in a phase transfer process. The invention is also directed to a method of copolymerizing 2-ethyloxazoline with such compounds. These monomers have an advantage over known 2-isopropenyl-oxazoline in their ability to be polymerized cationically without involvement of the vinyl groups and represent an improvement in the art over the following background references.
U.S. Pat. No. 3,563,920 relates to the ring-opening polymerization of bis-oxazoline compounds. The bis-oxazoline compounds contain sites of unsaturation.
U.S. Pat. No. 4,247,671 relates to vinyloxazolines which are polymerized through the vinyl group.
U.S. Pat. No. 4,103,093 relates to a polymer prepared from the copolymerization of an oxazolidinylethyl methacrylate, an alkyl methacrylate, and 2-hydroxyethyl oxazolidine.
U.S. Pat. No. 3,753,935 relates to a vinyloxazoline copolymer, wherein the oxazoline compound is polymerized through the vinyl group.
U.S. Pat. No. 3,464,933 relates to vinyloxazolines and copolymers derived therefrom.
U.S. Pat. No. 3,493,568 relates to polymers prepared by the ring-opening polymerization of hydroxyalkenyl oxazolines.
U.S. Pat. No. 3,493,635 relates to copolymers prepared from vinyloxazolines.
Poly oxazoline (POx) has been a material of considerable commercial interest. POx is useful in polymer additives. One of the most important physical properties of POx is its solubility. Thus, POx can be melt-blended with a number of thermoplastics (e.g, polyolefins, polyesters, saran, nylon). In addition, the excellent adhesive properties of POx may be utilized to improve adhesion of the thermoplastics to various substrates.
The synthesis of graft or block copolymers of POx is a logical approach to modify POx and maintain its bulk physical properties. The preparations of graft and block copolymers have been widely reported in literature. See T. Saegusa, H. Ikeda, Macromolecules, 6, 805 (1973); T. Saegusa, Makromolecular Chemie, 177, 2271 (1976), U.S. Pat. No. 4,001,147, both hereby incorporated by reference. Most approaches involve a polymer containing active halide groups or tosyslate groups (first stage) from where graft or block polymerizations (second stage) of oxazoline were conducted. This approach suffers low yield, slow polymerization rates, and generation of large amounts of Homo-POx. Furthermore, the preparation and purification (due to the nature of cationic polymerization of oxazoline) of "first stage" polymer is tedious and impractical. However, POx is prepared first and then in the presence of vinyl monomers, graft polymerizations are conducted by radical polymerization.
The present invention represents an improvement in the art, which will become evident to one having ordinary skill in the art on reading this entire specification, including the appended claims.